The semiconductor manufacturing industry is constantly seeking to improve the processes used to manufacture integrated circuits from wafers. The improvements come in various forms but, generally, have one or more objectives as the desired goal. The objectives of many of these improved processes include: 1) decreasing the amount of time required to process a wafer to form the desired integrated circuits; 2) increasing the yield of usable integrated circuits per wafer by, for example, decreasing the likelihood of contamination of the wafer during processing; 3) reducing the number of steps required to turn a wafer into the desired integrated circuits; and 4) reducing the cost of processing the wafers into the desired integrated circuit by, for example, reducing the costs associated with the chemicals required for the processing
In the processing of wafers, it is often necessary to subject one or more sides of the wafer to a fluid in either liquid, vapor or gaseous form. Such fluids are used to, for example, etch the wafer surface, clean the wafer surface, dry the wafer surface, passivate the wafer surface, deposit films on the wafer surface, etc. Control of the physical parameters of the processing fluids, such as their temperature, molecular composition, dosing, etc., is often quite crucial to the success of the processing operations. As such, the introduction of such fluids to the surface of the wafer occurs in a controlled environment. Typically, such wafer processing occurs in what has commonly become known as a reactor.
Various reactors have been known and used. These reactors typically have a rotor head assembly that supports the wafer. In addition to introducing the wafer into the processing chamber, the rotor head assembly may be used to spin the wafer during introduction of the processing fluid onto the surface of the wafer, or after processing to remove the processing fluid.
During processing, the wafer is presented to the rotor head assembly by a robot in a clean environment in which a number of processing reactors are present. The robot presents the wafer in an exposed state to the rotor head assembly in an orientation in which the side of the wafer that is to be processed is face up. The rotor head assembly inverts the wafer and engages and seals with a cup for processing. As the wafer is processed, the wafer is oriented so that the side of the wafer being processed is face down.
These types of reactors are useful for many of the fluid processing steps employed in the production of an integrated circuit. However, there remains a need for more control and efficiency from the reactor. As such, a substantially new approach to processing and reactor design has been undertaken which provides greater control of the fluid processes and provides for more advanced and improved processes.
An apparatus for processing a workpiece in a micro-environment is set forth. The apparatus includes a rotor motor and a workpiece housing. The workpiece housing is connected to be rotated by the rotor motor. The workpiece housing further defines a processing chamber where one or more processing fluids are distributed across at least one face of the workpiece by centrifugal force generated during rotation of the housing.
In one embodiment, the workpiece housing includes an upper chamber member and a lower chamber member joined to one another to form the processing chamber. The processing chamber preferably generally conforms to the shape of the workpiece and includes at least one fluid outlet at a peripheral region. At least one workpiece support is advantageously provided to support a workpiece in the processing chamber in a position to allow centrifugal distribution of a fluid supplied through an inlet opening into the process chamber. The fluid may be distributed across at least an upper face and/or lower face of the workpiece, when the workpiece housing is rotated. The fluid outlet is positioned to allow extraction of fluid in the processing chamber by centrifugal force.
In another embodiment, an apparatus for processing a workpiece includes a first rotor and a second rotor engageable with the first rotor to form a chamber for holding a workpiece and rotating the workpiece. A dividing member on one of the first and second rotors, extends radially inwardly at the circumferential edge of the workpiece. The dividing member allows for separating and reuse of the different fluids applied to the top and bottom surfaces of the workpiece.